I 15 over Int Seiben
GoodLewis and Clark County, Montana · 10M S Wolf Creek · Structure no. I00015216+04821
- Built
- 1962
- 63 years old
- Condition
- Good
- inspected October 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 115 ft
- 3 main spans
- Daily traffic
- 2,403
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 15 over Int Seiben is a prestressed concrete stringer/multi-beam or girder carrying I 15 over Int Seiben in Lewis and Clark County, Montana. It was built in 1962, so it is 63 years old, older than the Montana average of 47 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 2,403 vehicles a day, roughly 23% of them trucks, projected to reach 2,607 by 2043. The structure is 115 ft (35.1 m) long and 41 ft wide.
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 15 over Int Seiben built?
It was built in 1962, making it 63 years old in 2025.
What condition is I 15 over Int Seiben in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2024.
How much traffic does I 15 over Int Seiben carry?
About 2,403 vehicles per day (2023 count), of which roughly 23% are trucks.
How long is I 15 over Int Seiben?
The structure is 115 ft (35.1 m) long with a longest span of 40 ft (12.2 m) and a deck 41 ft wide.
Who owns I 15 over Int Seiben?
It is owned by the State Highway Agency.